In this program, nano-crystalline ceramics will be applied to the surface of orthodontic archwires using ion beam assisted deposition (IBAD) to reduce sliding resistance. Excessive sliding resistance works against tooth motion as the bracket slides along the wire into a new position, resulting in less predictable outcomes, and requiring increased force, treatment time, "chair time", and patient costs. Nano-crystalline IBAD ceramics will reduce friction in the couple, and more importantly, through hardening the arch wire, will eliminate the notching which occurs at binding points between the bracket and the wire, and exacerbates the typical stick-slip motion profile. Nano-crystalline morphology also yields a surface with improved toughness for withstanding wear. In this program, Al2O3, TiO2, and ZrO2 coatings will be applied to round and rectangular cross-section CuNiTi and 2Ti archwires, and compared to uncoated wires in a sliding resistance tensile test. The best material combinations appropriate for various treatment phases will be determined. Application of tough, adherent low sliding resistance coatings will effectively decouple sliding resistance from other mechanical properties of the arch wire. New combinations of mechanical and sliding properties will be made possible which will provide the practitioner with new tools for solving specific patient problems. PUBLIC HEALTH RELEVANCE: In this program, nano-crystalline ceramics will be applied to the surface of orthodontic arch wires using ion beam assisted deposition to reduce sliding resistance. Excessive sliding resistance works against tooth motion as the bracket slides along the wire into a new position. These ceramic coatings will produce more predictable outcomes, requiring less force, shorter treatment time, and decreased patient costs.